Episode 12 of "The Tale of Lady Ok" kicks off with Seung-hwi offering a heartfelt apology to Tae-young for the misunderstanding that had arisen between them. As he notices her bare feet, he sweetly scoops her up and carries her on his back, their bond evident in his gentle gesture. Their arrival coincides with Dokki and Mak-sim's tense confrontation, prompting Seung-hwi to reprimand Man-seok for meddling with Mak-sim. The slave stubbornly insists that he doesn't have feelings for her, but Dokki, in an unexpected twist, blurts out his affection for her, causing her to blush furiously.
Inside the residence, Do-gyeom seeks the truth from Mi-ryeong, who reveals her genuine affection for the Seung family. Suddenly, she starts bleeding, and they soon discover that her pregnancy was a false alarm. Terrified that Do-gyeom might believe she faked it, Mi-ryeong's anxiety is palpable. Tae-young and Seung-hwi confront Do-gyeom, who is actually relieved to learn that Mi-ryeong is fine. He promptly heads to her, stumbling upon her diary detailing their imagined "child." As she lambasts herself, expressing gratitude that the child would have a wonderful father, Do-gyeom breaks down in tears upon reading her heartfelt entries.
Seung-hwi can't resist teasing Tae-young for shielding Do-gyeom and concealing the truth, also warning her against interfering in Dokki and Mak-sim's blossoming relationship. Annoyed yet acknowledging his point, Tae-young finds herself oddly pleased that they can argue like a genuine couple. Meanwhile, Madam Hong returns to society's fold, while her husband grapples with the new magistrate—Kim Nak-su, So-hye's father. The magistrate, drunk on ambition, proposes planting eternal ginseng to enrich the county. Scholar Cha opposes the idea, but Hong gives it her blessing.
As for Mi-ryeong, she slips away, leaving behind an apology note. Do-gyeom, worried sick, embarks on a search that ultimately leads him to a courtesan house, where Mi-ryeong is now working as a waitress. He rescues her from a unruly customer, but she misinterprets his actions as pity. Finally, he confesses his enduring love for her and apologizes for pushing her away, his heartfelt words echoing through the room.
The couple, with Do-gyeom's impending assignment to Hanyang, maps out their relocation plans. A heart-wrenching farewell unfolds, with Tae-young's eyes welling up with tears. As Seung-hwi offers comfort to Tae-young, an observer stands by, silently witnessing the scene.
Elsewhere, Dokki is cast in a gloom, convinced that Mak-sim harbors affection for Man-seok. Frustrated by this perception, Seung-hwi, Man-seok, and Kkeutdong devise a scheme to help Dokki win Mak-sim's heart. They orchestrate a complete makeover for Dokki, tutor him in the art of penning a love letter, and present him with thoughtful gifts. Though flustered, Mak-sim is touched by Dokki's heartfelt gestures.
Concurrently, Hong fuels a rumor that Seung-hwi's chances of success are slim, as he faces competition from her son, Woong-yi. This spurs Tae-young to intensify her studies. In a moment of intimacy, they nearly share a kiss but opt to sleep apart until the exam. Seung-hwi harbors a wish, contingent upon his exam success.
The fateful day arrives. Woong-yi resorts to cheating and sails through, while Seung-hwi emerges victorious, topping the charts as the valedictorian and earning the title of Special Inspector. The Seungs celebrate with great grandeur.Dokki, shyly sharing a romantic glance with Mak-sim, hints at their budding romance. Tae-young, overjoyed, announces her intention to organize a wedding for them. The groom-to-be's nerves are evident, but his friends rally around him, cheering him up as they eagerly anticipate Mak-sim's arrival. When she finally steps in, delight fills the air. The wedding, though modest, is imbued with joy.
That serene night, Tae-young and Seung-hwi lie gazing at the stars from a nearby meadow. Tae-young inquisitively asks about his response to a political question, and Seung-hwi reveals that he learned from observing her adept handling of public petitions. He confesses his wish for them to consummate their love that night, assuring her that he'll be fine if she declines. She gently kisses his cheek, and their lips finally meet in a tender embrace.
However, the joyous days did not linger. Every resident in the county poured their investments into the mythical eternal ginseng, yet nothing flourished in return. The deceitful seller, Heo-soon, had vanished with their hard-earned money. Enraged, Scholar Cha, alongside Seung-hwi and Man-seok, marched towards the magistrate's office. To their astonishment, they encountered Nak-su, who found Seung-hwi's visage oddly familiar. Seung-hwi, adopting a disguise, introduced himself as Inspector Seung Yun-gyeom, while Man-seok hastily darted off to alert Tae-young. She had already preceded them to the office, summoned by complaints from her clients regarding the elusive ginseng. Her eyes widened in shock upon sighting Nak-su as well. Seung-hwi cleverly diverted Nak-su's attention, allowing Tae-young to slip away unnoticed. As The Tale of Lady Ok Episode 12 draws to a close, So-hye arrives to visit her father, unexpectedly bumping into her. Her face beams with joy as she affectionately addresses her as Gu-deok.
